Optical integrated reconfigurable mode generator-multiplexer for radio-frequency orbital angular momentum.

Radio-frequency orbital angular momentum (RF-OAM) mode multiplexing has received increasing attention in next-generation (6G) wireless communication as a new spatial multiplexing dimension to further extend data capacity. In particular, the circular antenna array (CAA) based RF-OAM generation using photonic methods is a promising approach due to its flexible reconfigurability, low propagation loss, high operating bandwidth, and high pattern quality. However, most current reports focus either on the bulk optics-based implementations or on band-limited delay line-based approaches.